<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Nov 24, 2008, at 4:17 PM, Zhongxing Xu wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">On Tue, Nov 25, 2008 at 3:03 AM, Ted Kremenek <span dir="ltr"><<a href="mailto:kremenek@apple.com">kremenek@apple.com</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> Hi Zhongxing,<br> <br> Why use the GDM to represent the byte extent of an AllocaRegion instead of storing it directly in the region object itself? I don't think it's necessarily a bad idea; I'm just curious about the overall design.</blockquote> <div><br>I don't have a definite reason for this. I feel that:<br><br>- The extent is not a necessary property of AllocaRegion (or the necessity has not showed). If we make it part of the AllocaRegion, that would require all clients provide an extent when creating the AllocaRegion.</div></div></blockquote><div><br></div><div>Just to clarify, what do you mean by "clients?" Different implementations of StoreManager?</div><br><blockquote type="cite"><div class="gmail_quote"><div>- Decoupling the extent of the dynamically allocated region provides more flexibility. Consider a MallocRegion, whose extent may be changed by a later realloc(). But its store bindings may not change. In that case, we can only modify the extent mapping of it.</div></div></blockquote><div><br></div><div>Makes sense.</div><br><blockquote type="cite"><div class="gmail_quote"><div>- If later we find the extent is an essential property of AllocaRegion, we can add it back.</div></div></blockquote><br></div><div>Absolutely. I wasn't arguing that we change it. All of this sounds good to me.</div><br></body></html>